Sustainability and Affordability with Lattices for Additive Manufacturing

MICHAEL STAIGER: Welcome to the presentation "Sustainability and Affordability with Lattices for Additive Manufacturing." My name is Michael Staiger. I'm working for One Click Metal, and I'm the technical sales manager and business development responsible for North America.

THOMAS STOCK: Hi. I'm Tom Stock, and I'm from Autodesk. And I'm an additive research engineer with quite a lot of additive expertise. But my main focus is laser powder bed fusion, and I've known Michael for a few years now. Brilliant. So on to the safe harbor statement.

And now I'll pass on to Michael to introduce One Click Metal.

MICHAEL STAIGER: Thank you, Tom. So quick introduction. Who is a One Click Metal? One Click Metal is a spinoff out of Trumpf, with the vision to make the metal 3D printing-- more people should have access to metal 3D printing, basically. And so we looked in the market and looked at the barriers, why not more people using this technology are like we developed a safer powder handling for the machine.

We tried to make this technology easier to use, and more intuitive, and also more affordable. And this is kind of also why we have a really good partnership to Autodesk because we kind of trying also to make the software really intuitive and also affordable, that more people have access to the software.

And also want to mention that our 3D printer was designed in Fusion 360. The whole design was made in Fusion 360. And you can also use Fusion 360 to prepare the job files, basically, from the beginning from your CAD file to your final job file, which you send to the machine. You can do all this stuff in Fusion 360 for the One Click Metal machine.

And also there are possibilities to develop some process parameter and so on. So this is to introduce a little bit One Click Metal and how we work together with Autodesk. And now I want to show you what we will cover in this presentation. And we have splitted this presentation in two parts.

One part is the introduction, and then the second part is we want to show you a use case. First of all, we want to introduce what is additive manufacturing and specifically to explain about the laser powder bed fusion process. The next is we want to explain what is a lattice, what is a lattice structure, and what are the benefits of this lattice.

And the last step is to show how we design lattices in Fusion 360. Then we jump to the next part, the use case, then we will give you an introduction into our application and about the challenges about this application. And then we want to show with this application a basic workflow in Fusion 360, how to use volumetric lattices.

And the second step is we want to give a more advanced way, a simulation-driven volumetric lattice in Fusion 360. And the last step is now we design the part in Fusion 360. Now we want to show how to prepare all the stuff to print out of this file and bring it to the printer, basically.

And the first step, Tom will give you an introduction into additive manufacturing.

THOMAS STOCK: Great. Thanks, Michael. So I know some of you will probably be familiar with the term "additive manufacturing." And some of you might not be, but some of you might be familiar with the term "3D printing." And 3D printing and additive manufacturing can be used interchangeably.

So additive manufacturing is one of the three main types of manufacturing processes. So we have formative manufacturing, which you can see at the top with the diagram. So it involves having a cavity or a mold and injecting your material into this cavity or mold. And then you will separate it to achieve your part.

And on the right, we can see an example of this. It's a hedge trimmer body case. Now, with subtractive manufacturing. You'll have a block of material. And you'll remove material with a cutting tool until you achieve the desired shape. And you can see on the right a simple bracket, which is typical for subtractive manufacture.

Now, finally, we have additive manufacturing. This process deposits material down and builds the part up in layers until you have your final end product. On the right, we have advanced generative design fixture. Perfect. And then next slide, please, Michael. So you know about additive manufacturing.

Now, what a lot of people don't realize is there's a huge range of additive technologies out there. So you can see on the left we have this little diagram. So you can see that these are the additive technologies available for just polymers. And you can see even for polymer there's different polymer types.

You can have it in liquid form. You can have in sheet form, pellet form, et cetera. And on the right, we can see the additive technologies suitable for metal. And we can see that we've indicated the laser beam powder bed fusion on the top right. And this is the additive technology that we're going to focus on today.

This laser beam powder bed fusion has some different names. It's also known as SLM, which is Selective Laser Melting. It's also known as DMLS, which is Direct Metal Laser Sintering. And it's also known as LMF, which is Laser Metal Fusion.

So it has a few different names, but we refer to it as laser powder bed fusion. And Michael will talk more to us about the process next.

MICHAEL STAIGER: Yeah. Thank you, Tom. Here's the graphic, what shows the laser powder bed fusion process. First of all, we need basically a job file for the machine. So we're taking a CAD file, and we are cutting this file in a lot of slices, in hundreds or thousands of slices. And we're sending this, basically, to the machine.

And here we can see the inner of the machine of a laser powder bed fusion machine. So we have in this machine a lot of metal powder here on the left side. So here is our supply, and on the right side it's basically where we are printing. So here is a platform on the bottom, and we are printing on top of this platform.

And as well, in the machine, we have a laser, some optics, some lenses, and some mirrors like a scanner. And we are basically moving the laser with these mirrors to the place where the part is. So we are exposing. We are melting the metal powder local where the part is. And where no powder is the powder stays as powder.

And if this is done, we're moving slightly one layer, one slice down with the platform. We're covering the whole platform with a new layer of powder. And then we start again with the laser to melt local the powder where the part is. And powder stays as powder.

And we're doing this layer by layer by layer. And after the whole print is done, after we finish the whole stack of slices, you can remove the unmelted powder. We're kind of cleaning the part from this unmelted powder. And then we have this parts left. Usually, they're stuck to the build plate, and we're removing them from the build plate, and then we have our finished part.

It's like the whole process for laser powder bed fusion. And also to show it a little bit easier, I have a video. It shows the printing process in our machine. So you can see on the top there's the laser jumping from part to part, exposing the powder, melting the powder locally.

And so if this is the whole layer is done, we're moving slightly down with the build plate. And now, again, we're covering the whole build plate with metal powder. And if this is done, we're again starting the laser, exposing in the next layer, starting again from the bottom to the top, melting local the powder.

And also I have this part with me, what we're right now printing. I hope we can see it good in the camera. So this is basically the part we are printing right now on the machine. So now we know a little bit about additive manufacturing and about the laser powder bed fusion process. Now I want to introduce what is a lattice.

So maybe with my German accent, it sounds lettuce and lattice, a little bit similar. So you can see on the top right we're not talking about a vegetable. We're talking about the structure, what you see here on the bottom. So, basically, we have a unit cell.

So this can look like this, basically a cross shape, or like a gyroid structure, or an X shape. And these are the unit cells, and we're kind of repeating this in a pattern in this unit cell. So we are using a lot of these unit cells and put it-- you can either filling a volume with this unit cell, or we can also modeling a surface of a part.

And so how does it work for a volume? You can see it here on the right. We have basically a box, a block of material, and we remove the inner shape of this. And we filled this shape with this lattice structure. So this is kind of what is the lattice and how we use these lattice structures in additive manufacturing.

And now Tom will explain to you about the benefits of this lattice.

THOMAS STOCK: Great. Thanks, Michael. So Michael described to us what is a lattice. And now I can talk through the benefits of using a lattice in additive manufacture. So the standard associated benefits of a lattice include less material.

So in the example that Michael just showed before, he talked about how an internal volume is often substituted for lattice structure. And therefore there's a lot of empty volume within that internal structure. It's partly lattice, partly empty air. And so there's less material used overall when printing the part, therefore also this benefits the print speed.

Because there's less material being used, because there's less structure to print, the prints also are faster. Because we're also using less material, there's a lightweighting effect. So because we talked about how that internal structure is partly air, partly lattice, there's a massive lightweighting effect of the part.

This, of course, leads to an increased performance. It may be for the aerospace industry or Formula One. And then there's also an aesthetics benefit. Lattices are quite cool to look at. They're visually impressive, and so they're quite alluring to the eye. Now I'll talk about the affordability side.

So we talked about how when we use the lattice there's less material used. Well, if we're using less material, there'll be less material costs. Second, because we're printing faster because there's less structure to print, we're able to fit more jobs per time. So this decreases cost, increase profit.

Thirdly, because we're printing jobs faster, we're doing things faster, there's a lower energy cost associated with the process. Finally, with the sustainability-specific benefits, we talked about how there's less material used. Now, the metal powder is very, very energy-intensive to produce. So by using less powder, we're also using less embodied energy.

Secondly, because the prints are faster and the machine is running for less time, there's a lower energy consumption. We also talked about the lightweighting effect. So because the parts have been lightweighted, more parts can be transported in one go, or, alternatively, the same number of parts can be transported, but there's a lower weight to the parts. And so overall there's lower transportation energy requirements.

Fourthly, there's lower machine operation energy. So what we mean by this is, say, for example, a robot will have an additively manufactured lattice part at the end. This part is lightweighted. And because it's lower mass, the robot will draw less energy to operate. If it was a fully dense part, then the robot would be drawing more energy to perform the same movements.

Finally, there's improved structural and thermal efficiency. So the latticing can provide a benefit by allowing a better energy cooling efficiencies, and therefore less energy is consumed in the process as a whole. Brilliant. So we've talked about the benefits. The next slide will talk about actually how we create lattices.

So latticing in Fusion 360. So we have our cube example here. And to create a lattice, we go to the volumetric latticing tool. We can select our body. And you'll see that immediately the lattice that we created can be manipulated straight away in the workspace. It's instant, and this is because the volumetric latticing tool uses something called implicit modeling.

Now, implicit modeling models geometry and controls the geometry via mathematical function as opposed to representing it as a surface, which is typical in normal CAD design. You can see we're changing effectively the density or the solidity, the lattice. And then, finally, we can also even give the lattice and offset.

So we can basically create a denser or sparser region. And we can give that a thickness and also give that a blend distance so they transition into each other. So you can see there's lots of possibilities with latticing in Fusion 360. And I'll pass back to Michael to give us the case study.

MICHAEL STAIGER: Yeah. Thank you, Tom. So now we finished our introduction. So now we know what is additive manufacturing. There are lot of technologies. We specifically talked about the laser powder bed fusion technology. And we talked about what is a lattice and how to use or how to generate lattice structures in Fusion 360.

So now we are ready to go to our second chapter. Now we come to our case study. We have a robot welding arm with us. And on this slide, you can see this robot arm. This robot welding arm is attached to a robot and is basically used in a automotive manufacturing line to weld some chassis parts together.

And so also you can see on the right side a zoomed-in photo, especially of this arm, so this light-blue-colored part we are talking about. So basically, on the left side, there's this shaft attached, the welding shaft attached. On the right on the upper side is basically where this welding arm is connected to the robot.

Yeah. So Tom will give you an introduction into this part and talk a little bit about the challenges of this application.

THOMAS STOCK: Great. Thanks, Michael. Yes. So as Michael said, this part is on a robot and is part of a large manufacturing assembly line. Unfortunately, this part is often prone to failure. And when this happens, of course, the assembly line is affected, and the assembly line production is affected as well.

And so there's an increased cost incurred to the company. Therefore, it's critical that when the part fails, it is replaced. Unfortunately, it's not always feasible to have a large inventory of spare stock of parts, especially if there's a lot of parts that could be replaced. It's better instead to manufacture on demand.

Now, manufacturing on demand and perhaps trying to improve the part function and having that time-critical factor in there suggests that additive could be a good possible solution. Additive also allows for more design and manufacture freedom and hence the possibility to use lattices.

MICHAEL STAIGER: Yes. Thank you, Tom. So now we know a little bit about the application. And now we have this part here. This is also designed with Fusion 360. Now we can see here the part in Fusion 360. And now we want to put some lattice structure into this part.

So now we see here the way how to do that, basically. Yeah. Go again to the volumetric lattice. We are selecting the body. And we want to select after that a cell shape like this unit cell. And so we can use here also a custom unit cell. You can see it on the bottom left.

We are using this cell shape, this cell type for this lattice structure. And to see it a little bit better, we are reducing here the solidity of this lattice structure. Now we generated the whole part in this lattice. Can take a look in there, and now we also want to maybe reduce a little bit the cell size.

So we make it a little bit smaller, and so now this is kind of the lattice structure. And we can also change the orientation of this also to increase the buildability of this part. So now the last step is you can see that here we can select faces on the part, where we just keep the normal structure, especially in regions where we connect the welding arm to the robot and where we connect it to this welding shaft, basically.

And here you can see a detailed view of this part, around the solid part. And in the middle, we can see this lattice structure, basically. And now we took this part, and we compared this part to the conventional part. So on the top left, you see the conventional part.

On the right side, you can see this part with less structure. And with this easy, basic workflow, we could reduce the material usage of about 40%. And we could reduce the print time by 26% because now we don't have to exposure that much surface, basically. And in total we could save about 34% energy.

And let's talk a little bit more about this energy saving, so in general, what already Tom mentioned in the beginning. So to produce this metal powder, it takes a lot of energy, basically. And so if we don't need that much material, we also save this energy because we don't have to produce the material.

The second step is kind of the manufacturing process. So during printing, we need also the machining, some energy, and so on. So we need a lot of energy during this manufacturing process. So we could also reduce this energy here. And in total we saved about 34% of energy just with this basic workflow and in Fusion 360 using this volumetric lattice tool.

So this is like the basic workflow, and also we have a more advanced workflow. And Tom will show you that now.

THOMAS STOCK: Great. Yes. So you've seen the more basic workflow from Michael using the volumetric latticing tool. Also, in Fusion, we can drive the volumetric lattice via simulation. And what I mean by that is you see we have the part on the left. And you can see on the right side of the part there's the two holes. These connect to the robot head.

And then on the left top side of the part, we have that other hole. And that's where the welding tool slots into. Now, during the spot weld process, there's a lot of force that goes into the structure or the parts surrounding the weld. And we try to simulate this in the middle picture.

So you can see that we've simulated the load cases. And the green and yellow areas indicate areas of higher stress. You can see on the left side of the part it's mostly entirely blue. And that indicates areas of lower stress. So we basically took this simulation data, we imported it back into the volumetric latticing tool in Fusion 360, and the image on the right shows the result.

So we have this relatively sparse lattice throughout the part. However, the important thing is that we can see in the regions where there is higher stress. So those green and yellow areas, there's a denser lattice in place. So the volumetric lattice tool has effectively created a denser lattice region to compensate for these higher-stress regions.

And we can see in the areas where there is lower stress in the part. So with these large blue areas, there's a relatively sparse lattice. Brilliant. And so that's kind of a great solution. And I'll pass on to Michael to talk to us about the metrics of that solution.

MICHAEL STAIGER: Yeah. Thank you, Tom. So here, again, we see in the top left the conventional part. And on the right, we see the simulation-driven volumetric lattice part. And here we saved with this about 43% of material, and we reduced the printing time with this about 27%, and in total energy savings about 36%.

So we can see that here is a really good tool to in general save material, time, and also a lot of energy, and as well cost, of course. So now we designed two parts, one with this basic volumetric lattice tool in Fusion. One is the simulation-driven volumetric lattice. And now we have this part designed, and now we want to print this part to have this part physical or [INAUDIBLE] to have it to where you can, in the end, use it.

So now Tom will show you about how to now take this part and to prepare everything for the print.

THOMAS STOCK: Great. Yeah. So as Michael said, we have the part. We've got it in the design workspace. If you want to manufacture the part, the first step we do is to always go into the manufacturer workspace. Then we create a setup.

And a setup is where we specify what machine and hence, therefore, what technology or additive technology we want to use. We need to also select Print Settings, but that's been automatically selected. And these print settings just determine how the part is printed.

Thirdly, we select Part, as we've just done, and click OK. Given the option to automatically arrange the part. And it places it more centrally in the build volume. But you can see at the top it's still outside that build volume. And so we're going to manually-- we can manually rotate it to make sure it fits entirely inside the build volume of the One Click Metal MPRINT+ machine.

Great. So that looks like it's fitted in. If we're happy, we can then hide the machine so we can have a better view of the part. And we can create our support structure. Support structures are an important process in most 3D printing technologies. And it's also the case for laser powder bed fusion.

So we can generate our volume support structure at the base of the part. And now we can generate our bar support at this area higher up the part, which needs more support. And we're going to choose a large bar to support this area to provide extra strength.

Fantastic. We'll reshow the machine, and we can double check that the part and the support structure is actually entirely in the build volume. Once we're happy, we can generate. And once we've generated the tool path and create build file, we can simply upload it directly to the One Click Metal MPRINT+ machine over the network, as shown here.

And once it's uploaded on the machine, we simply press Run, and the machine will build. So it really is an easy process to go from the design to manufacture to print with Fusion 360 to the One Click Metal MPRINT+ machine. And now pass it over to Michael to close.

MICHAEL STAIGER: Yeah. Thank you very much, Tom. And also thank you very much for joining our presentation.

THOMAS STOCK: Yeah. Thanks, all, for listening. Yeah. Thanks.